Syntax

Arguments

string_expression Is the string expression to be evaluated. string_expression can be a constant, variable, or column of either character or binary data.

Return Types

bigint if expression is of the varchar(max), nvarchar(max) or varbinary(max) data types; otherwise, int.

If you are using SC collations, the returned integer value counts UTF-16 surrogate pairs as a single character. For more information, see Collation and Unicode Support.

Remarks

LEN excludes trailing blanks. If that is a problem, consider using the DATALENGTH (Transact-SQL) function which does not trim the string. If processing a unicode string, DATALENGTH will return twice the number of characters. The following example demonstrates LEN and DATALENGTH with a trailing space.